N-heterocyclic carbene-based polymer coating of gold nanoparticles and luminescent quantum dots

We test the capacity of two N-heterocyclic carbene (NHC)-based metal-coordinating compounds that present polyethylene glycol solubilizing blocks, a polymer and monomer, as ligands for the surface passivation of colloidal gold nanoparticles, luminescent quantum dots, and iron oxide nanoparticles (IONPs) alike in water. The long-term colloidal stability of the NHC-stabilized nanocolloids has been tested following phase transfer to aqueous media, which presents a highly challenging environment for such groups, due to the moisture-sensitive nature of NHC molecules. We find that nanocrystals coated with these NHC-containing ligands exhibit long-term colloidal stability in buffer media with no sign of degradation or aggregation build-up, while preserving their photo-physical properties, for extended periods of time. Graphical abstract